Pros and cons of underground and overhead cables

I have to make a poster thats in for tomorrow about the pros and cons of overhead and underground cables!!!
Does anyone know what they are???
I cant find much info anywhere!!
Thanks Becz x

pros on over head :
easily installed
easy to fix if a problem occurs
costs less

cons:
easily damaged (for example if anything heavy falls on them)
hazards to people if a cable is cut and falls on the ground
will take up space for the poles on the road and they can be dangerous as well if they are damaged (may fall on people)

pros on underground:
hard to damage since they arent accessible to people
also safe from weathering etc.
if a wire is cut there is no threat of damaging people or animals

cons:
cost more
maintenance is harder
earthquakes (even small ones) may damage the wires

these were all I could remember from my classes a few years ago...never did like being an electrician

thanks so much!!!